This invention relates to a towing system for a trailer, particularly a towing system that can be economically changed to utilize either a fixed non-damped towing mechanism or a damped towing mechanism. The term fixed non-damped denotes a rigid, nonextensible connection between the trailer and towing vehicle. The term "damped" denotes a hydraulic shock-absorber type connection between the trailer and towing vehicle.
For trailers in which the longitudinal inertia forces are relatively constant, a fixed non-damped connection between the trailer and towing vehicle is satisfactory. However, where heavy trailer loads or varying trailer inertia forces are encountered it is desirable to employ a damped connection between the trailer and towing vehicle. Varying inertia forces are commonly associated with liquid tank trailers or heavy cargo trailers, such as boxed ammunition carriers. The liquids in tank trailers can slosh or surge back and forth out of phase with trailer motion to provide objectionable intermittent pulse loadings on the towing connection. By incorporating a hydraulic shock absorber or dampener in the towing connection it is possible to absorb these pulse-type loadings in the towing connection, thus improving human driver comfort as well as increasing the structural life of the towing mechanism and other vehicle components, such as the brakes and suspension.
The present invention contemplates modifications to a convention two wheel A-frame trailer front end to enable the A-frame to receive either a fixed non-damped towing system or a damped towing system. Towing system interchangeability is especially useful in military vehicles where a given vehicle may be required to handle different types of cargo from one day to the next. Towing system interchangeability is further advantageous in such respects as lower depot inventory requirements, easier repair or maintenance operations, and capability for accommodating design improvements in towing system hardware without alterations in the trailer A-frame.